Find Unit Vector and Angel

Suppose that you are climbing a hill whose shape is given by , and that you are at the point (90, 50, 300).

In which direction (unit vector) should you proceed initially in order to reach the top of the hill fastest? ,
If you climb in that direction, at what angle above the horizontal will you be climbing initially (radian measure)?
__________.

Suppose that you are climbing a hill whose shape is given by , and that you are at the point (90, 50, 300).

In which direction (unit vector) should you proceed initially in order to reach the top of the hill fastest? ,
If you climb in that direction, at what angle above the horizontal will you be climbing initially (radian measure)?
__________.